So you are building this yourself? Try the linux_xorg7 binaries.
If they work (as I expect) there is probably something wrong with
your compilation, probably with the compiler's optimization (we
see that once in a while).

1. Try it from either the full xorg7 package:

wget [afni.nimh.nih.gov]

2. OR, just get the current 3ddot program:

wget [afni.nimh.nih.gov]
chmod 755 3ddot

3. Assuming 3ddot works correctly in the downloaded version,
try adjusting the optimization on compiling 3ddot.c -> 3ddot.o,
dropping it down one level (or starting with even -O0, just to
be sure).

Note that you might need to recompile all of libmri.a, if 3ddot.o
does not help.

If you know it comes from the optimization, that still makes
your life a little difficult. Maybe downloading would be better?

- rick